Ultraviolet Germicidal Irradiation (UVGI) Systems, Making Guests, Clients, Patients, Visitors and Employees Safer by Reducing Risk of Virus Spread. The UVGI Stand-alone Mobile Filter Unit is suited where a permanent installation is impractical and can be moved to any area requiring Germicidal Irradiation. The volume of the space dictates the air changes per hour, the units are designed to be operated continuously to filter airborne pathogens and that we can add multiple units in a space as needed to provide additional filtration.